Patch and method of making the same



A. MORTON ET AL m-cri AND mmaon OF MAKING THE SAME Filed may 14 1921 Imuemfarw Jfizmld A. Jim m3,

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rarer arena more) A. monron AND MARION n. nannrson, or ram, onrc, assreuons TO can when arenas. comranr, or Amen, owe, a coaronarron' or onto.

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Application flied May 14, 1921. serial No. MWMB.

Tocllcvhom iii may aonoem:

Be it known that we, HAROLD A. Monron and MARION M. HARRISON, citizens of the United States, and residents of Akron, in the county of Summit and State of Ohio, have invented certain new and useful Improvements in Patches and Methods of Making the Same, of which the following is a s ecification.

ur present invention relates to improvements in patching material designed for patchin or repairin punctured inner tubes of vehic e tires and t he like, and the invention aims to provide patching material which will possess ample elasticity to make it suitable for application to the elastic inner tubes, and which will retain for an indefinite period the necessary characteristics or condition which will enable it to be efiectively used as a patching medium.

The .invention further aims to provide patching material of laminated nature in which the laminations will be permanently united and yet .possess a surface layer of unvulcanized material which will remain permanently vunvulcanized, so that upon application of a suitable solvent a cement will be formed on the surface of the patch capable of adhering to the tube to be repaired.

With these and other objects in view,

the invention comprises the novel patching material and method of forming the same hereinafter described and particularily defined by the appended claims.

Our invention is illustrated in the accompanying drawing, in 'which Figure 1 is a plan view partly broken away showing a strip of patching material,

and 1 Fig. 2 is a section on'line 2-2 of Fig. 1.

Our improved patching material is preferably manufactured in sheet form and of a size sufiicient to enable a number of patches to be cut therefrom of the varying sizes according to the size of the puncture to be repaired, and such a sheet isshown in the accompanying drawing, vious that the size 0 the sheet is immaterial, and if desired, might bein the shape of individual patches instead of a larger but it will be ob-- ing sulphur, another from a rubber compound containing an organic accelerator, and the third from a rubber stock containin neither sulphur nor accelerator. The en phur and accelerator containing layers are superimposed one upon the other, and the third layer is applied to the surface of one of the first mentioned layers, preferably upon the layer containing the accelerator, as shown in Fig. l, in which the numeral 1 designates the sulphur containing layer, the numeral 2 the accelerator containing layer, and the numeral '3 the layer containing neither sulphur nor accelerator. A layer of holland cloth 4 is applied to the exposed surface of the third layer'where it remains until the patch is used.

,point of junction with the layer 2.

In the manufacture of our improved patch, we form the layer 1 by the use of any suitable rubber mixin apparatus, and calender, not necessary to e shown herein, from a rubber compound containing sulphur but no accelerator, and the layer 2 in a similar manner from a rubber compound containing an accelerator, but no sulphur.

Assuming the layers 1 and 2 to be of approximately equal thickness, which" is preferable the layer 1 would contain an amount of .sulphur necessary to effect the vulcanization of a sheet of aggregate thickness of layers 1 and 2, but no more, while similarly the sheet 2 would contain a quantity of accelerator capable of coacting with the sulphur to effect the vulcanization of the :sheet of ag egate thickness of lzgers 1 and 2. The yer 3 is then appli to located between the the surface of. one

fabric 4 placed over the bee and this must migrate words, it will not be liable of. the layers 1 or 2 and the protedzive exposed surface of the layer 3. Thereafter the compositeshcet is subjected to a temperature suiiiciently high to eifect vulcanization and under the action of the increased temperature the sulphur and accelerator te, so that they interact to efi'ect the canization of the two layers 1 and 2 and their union, and also unite the surface of the layer 3 to one of the aforesaid layers vulcanization of the layer. 3. It will be understood that proportions of sulphur and accelerator are so selected that vulcanization takes place at a low or what may be termed room tem erature. The proportions of sulphur an accelerator being only suficient to effect the vulcanization of the layers 1 and 2 and the vulcanization thereof by vulcanization without such afiecting the body to the surface of the layer 3, it will be ap-' parent that there is no possibility forthe body of the layer 3 to become vulcanized, and it will therefore remain in its unvulcanized condition, so that upon the stripping off of the protective muslin and the apphcation of the solvent, such as gasoline, thereto, the necessary cementing surface will be formed for adhering to the tube to be patched.

For" example, posed upon the accelerator carrying layer, it will be apparent that accelerator alone cannot migrate into the layer 3 to effect vulcanization of the latter, which could only take place by the presence of sulphur, but as the sulphur containing layer is separated from the layer 3 by the accelerator bearing portion, the migrate through the intervemng. layer to reach the layer 3, but by the time it has migrated through the intermediate layer, it has been completely combined with the rubber or acted upon thereby, so that there is no free sulphur left to act upon the third layer. Similar if the sulphur bearing layer is third layer and the accelerator the presence of the sulphur adjoining the third layer could not affect it, as the lower heat used will not enable layer 3 to vulcanize in the presence of sulphur alohe, the action of the accelerator being necessary,

through the intervening strip, and by the time it has so migrated and reached the surface of the third layer, it has been completely used up.

We have found that by the process above descri 'we can secure a patch which possesses ample elasticity, one in which the layers are firmly united together by vulcanization, and one in which the surface layer will be of unvulcanized material, which condition it will retain indefinitely or in other to' become subsequently vulcanized or hardened, and we if the layer 3 is superim sulphur would have to b l thereb avoid serious objections which have n ound of which we are aware.

Examples of layers which we have satisfactory are as follows:

The sulphur-containin layer sist of the following compound:

Smoked sheets 73.75 Sul hur 1.25 L1 ophone 20.00 Zinc oxide ..a 5.00

The accelerator-containing layer may be composed of:

sulphide 0.75 I The uncured layer may consist of:

Smoked sheets Q 75.00 Lithophone 25.00

The patch formed by superim above layers may be cured four hours at 60 C.

, Having thus described our invention what we claim is: 7

1. The hereindescribed method of formg a sheet of patching material which consists in superimposing on each other a plurality of layers of rubber compound, one outer layer containing neither sulphur nor accelerator, the other layers contaming respectively an accelerator and sulphur, the proportion of sulphur and accelerator being may conthe a anced so as to be just suflicient to efiect vulcanization of said last two layers and their union by vulcanization to the first named layer, lea said first named layer unvulcamzed, and ereaftgr effecting such vulcanization.

2. The hereindescribed method of forming a sheet of patching material which consists in superlmposing on each other a plurality of layers of rubber compound, one outer layer containing neither sulphur nor accelerator, an intermediate layer containing an accelerator, containing sulphur, the vulcanization of their union' by named layer.

3. A laminated sheet of patching material 'comprisin alayer of tainm phur but no accelerator,.a layer of'rub r compound containing accelerator but no sulphur, and a layer of rubber'compound contammg neither sulphur nor acand thereafter efi'ectmg the last two layers'an celerator, assembled in the order named and heat at a temperature less than found vulcanization to the first rubber compound com,

to patches heretofore produced 7 or twentyand the other outer layer v 4. A luminotedsheet of patching materiel first named layer when the assembled layers oomprising slayer oirnbber compound oonare subjected to vuloenizing hoot.

toimng neither sulphur noroooelentor, o In testimony wh layer containing sulphur; an intermediate; natures. o loyer,containing aooelerotorbutno sulphur r 1 r and noting to prevent sulphur from mi v HAROLD-A. MORTON. from the mound nomedloyerto' the MARION M. HARRISON.

ereof, we aflix our sig- 10 

